﻿<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>html5悬浮圆圈背景动画特效 - 站长素材</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">

<style>
body {
    background-color: #FFFFFF;
    /*background-color: #f4f4f4;*/
	margin: 0px;
	overflow: hidden;
}
.LoR {
	height:205px;
	width:164px;
	overflow:hidden;
	/*background:url(images/logo.png) 0 0 no-repeat;*/
	position:absolute;
	top:50%;
	left:50%;
	margin:-102px auto auto -82px;
	z-index:2;
}
</style>

    <script type="text/javascript" src="js/three.min.js"></script>

</head>
<body>


<script type="text/javascript">
var container;
var camera, scene, projector, renderer;
var PI2 = Math.PI * 2;

var programFill = function ( context ) {
	context.beginPath();
	context.arc( 0, 0, 1, 0, PI2, true );
	context.closePath();
	context.fill();
}

var programStroke = function ( context ) {
	context.lineWidth = 0.05;
	context.beginPath();
	context.arc( 0, 0, 1, 0, PI2, true );
	context.closePath();
	context.stroke();
}

var mouse = { x: 0, y: 0 }, INTERSECTED;

init();
animate();

function init() {
	container = document.createElement( 'div' );
	container.id = 'bgc';
	container.style.position = 'relative';
	container.style.zIndex = '0';
	document.body.appendChild( container );
	camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 1, 10000 );
	camera.position.set( 0, 300, 500 );
	scene = new THREE.Scene();

	for ( var i = 0; i < 100; i ++ ) {
		var particle = new THREE.Particle( new THREE.ParticleCanvasMaterial( { color: Math.random() * 0x808080 + 0x808080, program: programStroke } ) );
		particle.position.x = Math.random() * 800 - 400;
		particle.position.y = Math.random() * 800 - 400;
		particle.position.z = Math.random() * 800 - 400;
		particle.scale.x = particle.scale.y = Math.random() * 10 + 10;
		scene.add( particle );
	}
	projector = new THREE.Projector();
	renderer = new THREE.CanvasRenderer();
	renderer.setSize( window.innerWidth, window.innerHeight );
	container.appendChild( renderer.domElement );
	document.addEventListener( 'mousemove', onDocumentMouseMove, false );
	window.addEventListener( 'resize', onWindowResize, false );
}

function onWindowResize() {
	camera.aspect = window.innerWidth / window.innerHeight;
	camera.updateProjectionMatrix();
	renderer.setSize( window.innerWidth, window.innerHeight );
}

function onDocumentMouseMove( event ) {
	event.preventDefault();
	mouse.x = ( event.clientX / window.innerWidth ) * 2 - 1;
	mouse.y = - ( event.clientY / window.innerHeight ) * 2 + 1;
}

function animate() {
	requestAnimationFrame( animate );
	render();
}
var radius = 600;
var theta = 0;

function render() {
	// rotate camera
	theta += 0.2;
	camera.position.x = radius * Math.sin( theta * Math.PI / 360 );
	camera.position.y = radius * Math.sin( theta * Math.PI / 360 );
	camera.position.z = radius * Math.cos( theta * Math.PI / 360 );
	camera.lookAt( scene.position );
	// find intersections
	camera.updateMatrixWorld();
	var vector = new THREE.Vector3( mouse.x, mouse.y, 0.5 );
	projector.unprojectVector( vector, camera );
	var ray = new THREE.Ray( camera.position, vector.subSelf( camera.position ).normalize() );
	var intersects = ray.intersectObjects( scene.children );
	if ( intersects.length > 0 ) {
		if ( INTERSECTED != intersects[ 0 ].object ) {
			if ( INTERSECTED ) INTERSECTED.material.program = programStroke;
			INTERSECTED = intersects[ 0 ].object;
			INTERSECTED.material.program = programFill;
		}
	} else {
		if ( INTERSECTED ) INTERSECTED.material.program = programStroke;
		INTERSECTED = null;
	}
	renderer.render( scene, camera );
}
</script>

<div class="LoR"></div>

</body>
</html>